1. Field
The present invention relates to an endoscope, and more particularly, to an endoscope having a structure that is capable of smoothly performing insertion, while securing the visual field of the endoscope, even when a cap is coupled.
2. Description of Related Art
It is important to find cells that may proceed to a colorectal cancer, such as polyps of large intestine of internal organs of the human body. To attain this end, in general, colonoscopy is performed, and to find a cell, such as a polyp, it is very important to increase the detection rate of polyp.
However, because the inner walls of the large intestine are folded and curved, there was a difficulty in smoothly taking pictures of the inner wall surfaces using the endoscope. When taking pictures of the inner walls of the large intestine folded in a zigzag manner at the time of the conventional large intestine endoscopy, the detection rate of polyps may be lowered by about 20% to 30%. Therefore, in order to solve this problem, a tubular shape made of a transparent material was coupled to a front end of the endoscope. When taking pictures of the endoscope in the status in which the cap is coupled in this way, it is possible to take pictures of the inner walls, while pushing to flatten the winding large intestine inner walls away using a cap.
However, when inserting the endoscope while the cap is coupled, there was a problem in which the visual field of the endoscope may be narrowed, and time taken for insertion may become longer. In particular, in the case of the large intestine endoscope, at the time of insertion, there is a need for a cap in which a length of the endoscope front end to the front end of the cap is long, and conversely, at the time of recovery of the endoscope, there is a need for a cap in which a length from the front end of the endoscope to the front end of the cap is short. However, the length of the cap may vary depending on proficiency and preference of physician who performs procedure of colonoscopy. Therefore, it is necessary to develop an endoscope having a structure that is capable of smoothly performing the insertion, while ensuring the visual field of the endoscope even when the cap is coupled.
Accordingly, to solve the aforementioned problems of conventional techniques, an object of the present invention is to provide an endoscope that can increase the detection rate of polyp, by controlling the length of the cap depending on various situations of practitioner at the time of the endoscopy, and can smoothly insert the endoscope, while ensuring the visual field of the endoscope even when the cap is coupled.